This invention relates to disposing the braid of a coaxial cable over a ferrule and in particular to a method and apparatus for achieving a more uniform lay of the braid of a coaxial cable around the ferrule resulting in improved electrical and mechanical performance of the resulting coaxial contact.
There is disclosed in U.S. Pat. Nos. 4,990,104 and 4,990,105 a coaxial contact, as well as an electrical connector in which the coaxial contact may be secured, securable to a coaxial cable having a coaxial center conductor separated from an outer conductor or braid by an insulator, with an insulative jacket surrounding the braid. The coaxial contact has a center contact terminable to the center conductor of the coaxial cable. An insulative insert is positioned around the center conductor and a ferrule is positioned thereover. The braid of the coaxial cable is positioned surrounding a portion of the ferrule and a shell is crimped onto the portion of the ferrule over which the braid is positioned. This crimp mechanically secures the coaxial contact assembly together and provides electrical continuity between the braid and the ferrule.
The method of assembly and resulting coaxial contact described above has been found to have strands of the braid that are not uniformly distributed around that portion of the ferrule covered thereby. In addition, occasionally braid strands are severed by the crimping process or swaged so as to be weakened. This necessitates more attention be given to tooling set up or the crimping process and more care and hence more time by the contact assembler. Some weakened braid strands subsequently fail or shear during handling in subsequent assembly operations such as during insertion of a coaxial contact into an electrical connector, during handling or flexure of the resulting cable assembly or during later removal or insertion of the coaxial contact from or into the connector housing. Such failure of braid strands is undesirable as it diminishes the electrical performance of the coaxial contact.
It would be desirable to be able to more uniformly lay the braid strands over the ferrule in an efficient manner and effect the crimping of the shell thereover in a manner that improved mechanical and electrical characteristics of the resulting contact.